madara space/time jutsu is more advance than the fourth according to kakashi( said so during the sasuke vs itachi arc) Also where is everyone getting this idea that madara copied the fourth space/time jutsu in the first place? If you think about it, madara's tech is a highly advance version of what kakashi use to do with MS, except madara can make his own body go to another dimension at whim.
Also side notice minato refers tobi being present in the shadows 16years ago. So madara was still wearing the mask when he was controlling the kybui. Which leads me to believe he lost that other eye fighting the 1st, making another reason for him being only a mere shell of his former self.